Are the pci-e 2.0 16x slots longer than the pci-e 2.0 4x slots? Just checking to see if my motherboard has 2 pci-e 16x slots to run crossfire. This is the motherboard: ASUS P8Z68-V LX LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS
The PCI slots are the same length. The 16x and 4x designations are there to tell you how many channels that slot will have to transfer data in a specific designation. Are you having problems using a single 6950? What are you using your computer for?